The elevated temperature erosion behavior of HVOF tungsten carbide cermet coatings

Conference · Sat Dec 30 23:00:00 EST 1995

OSTI ID:379592

Wang, B Q ^[1]

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1. Metalspray USA, Inc., Richmond, VA (United States)

A series of elevated temperature erosion tests was carried out on HVOF Wc-17Co cermet coating specimens at 300 C and 450 C at particle velocities of 30 m/s and 60 m/s and at impact angles of 30{degree} and 90{degree}, using bed ashes and fly ashes retrieved from operating CFBC boilers. The elevated temperature erosion behavior of HVOF WC-17Co coatings was compared with those of AISI 1018 steel, and other thermal sprayed coatings including a HVOF 75%Cr{sub 3}C{sub 2}-25%NiCr cermet coating, an arc-sprayed FeCrSiB metallic coating and a flame-sprayed Cr{sub 2}O{sub 3}-6SiO{sub 2}-4Al{sub 2}O{sub 3} ceramic coating. The morphologies of specimens were examined by light microscopy and scanning electron microscopy (SEM). The microhardness of the surface of the specimens was measured. It was found that the hardness of the coatings had no direct relationship with erosion-corrosion wastage and the erosion behavior of coatings is closely related to their microstructure and composition. In general, the coatings with larger splat size, coarse and heterogeneous structure, higher porosity and the presence of craze cracks or inclusions have the higher erosion wastage. However, the effect of microstructure of coatings on the erosion behavior varied with erosion test conditions.

• OSTI ID: 379592
• Report Number(s): CONF-9509182--; ISBN 0-87170-541-9
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM OXIDES
BORON ALLOYS
CERMETS
CHROMIUM ALLOYS
CHROMIUM CARBIDES
CHROMIUM OXIDES
COBALT
CORRELATIONS
CRACKS
EROSION
FLY ASH
IRON ALLOYS
MICROHARDNESS
MICROSTRUCTURE
MORPHOLOGY
NICKEL ALLOYS
OPTICAL MICROSCOPY
PROTECTIVE COATINGS
SCANNING ELECTRON MICROSCOPY
SILICON ALLOYS
SILICON OXIDES
STEELS
TUNGSTEN CARBIDES